Multifunctional metal-organic frameworks with photothermal-triggered nitric oxide release for gas/photothermal synergistic cancer therapy.

Photothermal therapy (PTT) utilizing cyanine dyes (Cy) and nitric oxide (NO) gas therapy via BNN6 have demonstrated significant potential in cancer treatment. However, the rapid clearance of these small molecules from the body limits their accumulation at tumor sites, thereby reducing therapeutic efficacy. To address this, we employed the acid-sensitive nanomaterial ZIF-8 as a carrier to encapsulate Cy and BNN6, creating functionalized BNN6-Cy@ZIF-8 Nanoparticles (B-C@Z NPs) for the targeted delivery and release of Cy and BNN6 at tumor sites. Within the acidic tumor microenvironment and lysosomes, ZIF-8 degrades, releasing Cy and BNN6. Under 808 nm laser irradiation, Cy exhibits excellent photothermal conversion efficiency, generating substantial heat to induce tumor cell apoptosis via PTT. Simultaneously, the elevated temperature triggers the decomposition of BNN6, releasing NO to further enhance tumor cell cytotoxicity. This synergistic approach, combining hyperthermia and NO-mediated cytotoxicity, has shown near-complete tumor eradication in vivo and in vitro, offering a promising novel strategy for cancer therapy.